The picture quality implications of low bit-rate terrestrial television

The author seeks to determine the likelihood of HDTV broadcasting on a terrestrial channel using low bit-rate picture coding techniques. A two-stage approach to scene-dependent quality characterisation accounts first for statistical variation of criticality in typical television, and then determines viewers´ tolerance of occasional picture distortion. The importance of a hierarchical coding and decoding environment is discussed, with the basic ideas of subband coding. A consideration of graceful degradation of quality in adverse transmission conditions includes the principles which could make this a feature of all-digital television transmission